title: Enhanced NIR downconversion luminescence by precipitating nano Ca5(PO4)3F crystals in Eu2+-Yb3+ co-doped glass.
abstract: Eu(2+)-Yb(3+) co-doped transparent glass-ceramic containing nano-Ca5(PO4)3F (FAP) was prepared in reducing atmosphere. XRD and TEM analysis indicated that nano-FAP about 40 nm precipitated homogeneously in glass matrix after heat treatment. Confirmed by spectroscopy measurements, the crystal-like absorption and emission of Eu(2+) indicated the partition of Eu(2+) into FAP nanocrystals in glass ceramic. NIR emission due to the transition (2)F5/2→(2)F7/2 of Yb(3+) ions (about 980-1100 nm) was observed from glasses under ultraviolet excitation, ascribed to downconversion from Eu(2+) to Yb(3+), which can be enhanced by precipitating nano-FAP crystals. The results indicated that Eu(2+)-Yb(3+) co-doped glass-ceramic embedding with nano-FAP is a promising candidate as downconversion materials for enhancing conversion efficiency of solar cells.
authors.affiliation: School of Materials Science and Engineering, Kunming University of Science and Technology, Xuefu RD, Kunming 650093, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Song
authors.forename: Yongjin
authors.initials: Y
authors.lastname: Li
authors.forename: Kai
authors.initials: K
authors.lastname: Lou
authors.forename: Jianbei
authors.initials: J
authors.lastname: Qiu
authors.forename: Zhengwen
authors.initials: Z
authors.lastname: Yang
authors.forename: Zhaoyi
authors.initials: Z
authors.lastname: Yin
authors.forename: Xue
authors.initials: X
authors.lastname: Wang
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.forename: Ronghua
authors.initials: R
authors.lastname: Wan
mesh_terms: D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry; D011232:Chemical Precipitation; D003460:Crystallization; D005063:Europium / Q000737:chemistry*; D017611:Fluorine Compounds / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D049449:Luminescence; D008163:Luminescent Measurements; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D019265:Spectroscopy, Near-Infrared; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D002130:Calcium Phosphates; D017611:Fluorine Compounds; D005063:Europium; C020243:calcium phosphate; D015018:Ytterbium
keywords: Cooperative energy transfer; Downconversion; FAP; Nano-glass–ceramic